Introduction:

Wheels & Axles offer another example of a force distance tradeoff. Sometimes the input is on the wheel, to put a larger force on the axle, and sometimes the input is on the axle, to give a distance advantage to the wheel.

Activity:

Try the tinkertoy wheel/axles provided by your teacher. Explain the force-distance trade-off involved.

The Essence of The Pulley:

• A rope moves smoothly over one or more surfaces to change the direction or amount of force required to move somthing.
• MA = (Input Distance) / (Output Distance) (Note: For lifting pulleys, the MA equals the number of ropes supporting the weight.)

Video of 2007 RGD

Conclusion:

Start to look for materials that could be used as simple machines! Start to collect junk for your RGD!